Police Lt. Robert Kennedy was one of several people, including a businessman, charged earlier this month with sexually assaulting the teen.

Lt. Christopher Corbett, a police spokesman, said Kennedy was fired Friday after an internal investigation. Corbett said Kennedy tried to quit but his resignation was not accepted.

The investigation started after the boy's father told an inspector in Waterbury State's Attorney John Connelly's office that he was worried about his 15-year-old son hanging around late at night at Library Park and Hamilton Park.

Kennedy, 46, a Waterbury native, joined the department in 1995. He had been on paid administrative leave.

Kennedy is charged with first-degree sexual assault, second-degree sexual assault, fourth-degree sexual assault and three counts of risk of injury to a minor. He is free on bond and is due back in court June 13.